1. Field of the Invention
This invention relates generally to digital image processing, and more particularly to devices used for processing neighbor images.
2. Description of the Prior Art
No memory IC yet has been proposed in the art which, in an image neighbor process, can read the image neighbors at the same time.
That is, heretofore a method generally has been employed in which neighbors (picture elements) are sequentially read out of a single memory, and accumulated in a shift register, so that the neighbors may be obtained simultaneously.
FIG. 3 is a circuit diagram showing one example of a conventional neighbor image processing device.
The conventional device has a plurality of series-connected shift registers, each corresponding to one horizontal line. Image data sequentially read out of the image memory are stored in the shift registers. The data are loaded in a read tap register through the intermediate connecting points of the shift registers, and neighbor data read out in a parallel mode are applied to an arithmetic unit array or the like. Thus, the operation is performed in the manner of a pipe line, to obtain the outputs sequentially or one by one.
The example shows the case of image-processing of 3.times.3 neighbors.
The sequential outputs thus obtained are written in the image memory so that they may be processed later.
The above-described conventional neighbor image processing device in which neighbors (picture elements) are picked up and processed with the aid of the image memory and the shift registers suffers from the following difficulties:
1. Since the shift registers are fixed in length, it is difficult to vary the configuration of a neighbor region which is selected.
2. Since the image data must be input sequentially, random access is not possible.
3. In order to pick up a larger neighbor region, it is necessary to add hardware.
Accordingly, it is an object of this invention to access neighbor image data randomly rather than sequentially for subsequent processing.
Another object of this invention is to process neighbor image data of varying configurations.
It is a further object of this invention to increase the capacity of a neighbor image processing memory device without the need for significant additional hardware.
Additional objects and advantages will be obvious from the accompanying description, or may be learned by practice of the invention.